Research

Dr. Toma's Research Projects

My research interests are genetics and behavior, broadly speaking. For a while, I have been involved in a behavioral-genetic analysis of geotaxis in Drosophila. However, I have recently begun an analysis of gene expression in cattail (Typha) taxa with Dr. Brad Cook of the Biology Department at MNSU.

Drosophila genetics

My work with Drosophila studies lines of flies selected for extreme geotaxis (response to gravity) behavior. One line goes up away from gravity in a t-choice maze (the Hi line) and the other goes down toward gravity, the Lo line. These lines of flies were selected in now classical experiments by Jerry Hirsch and Theodosius Dobzhansky in order to investigate the nature of the genetic basis for this behavior. Their work with these lines constituted the first attempt at the genetic analysis of a complex, polygenic behavior, and demonstrated a genetic basis for geotaxis and by implication, behavior in general. Prior to coming to MNSU, I studied global gene expression in the brains of the Hi and Lo lines to investigate how gene expression in the brain influences behavior. Since I have come to MNSU, I have decided to put my efforts into two behavioral projects with these flies. The first project compares individual vs. group behavior in both lines. Since the flies were selected as populations of flies going up or down in the maze, the question asks whether there was a concomitant selection of individuals to go with the group in running through the maze: is there a group effect in this behavior? Other questions with of interest with this project are what are the sensory modalities and genes mediating a group effect in these flies. My second project with these fly lines is to determine a circuitry map of the behavior in the brain. This is longer term work and uses the versatility of the Drosophila system to selectively turn off or hyper-excite various brain regions of the Hi and Lo flies.

Typha genetics

I am also involved in a plant genetic project with Dr. Brad Cook (Biology Dept, MNSU). We are interested in examining differential gene expression between three cattail taxa (native American, introduced European, and their hybrid) as a model organism for biofuel production, nutrient mitigation, and species invasiveness. This will be done using a mass sequencing approach of the expressed genes of the three taxa at the genomics facility at the University of Minnesota in order to identify differential gene expression. Candidate genes will then be further studied to see if they contribute to traits of interest. A grant from the Institute for Research on Energy and the Environment at the University of Minnesota was awarded to conduct this work.